Although the era Genroku (1688 - 1704) of the inscription is corroded and illegible the cyclic dating of the two characters mizunoto and tori, and the indication of the sixth year of the era, combine to identify the date as 1693. The signature on the helmet, despite the last character of the name being obliterated by rust, is most certainly that of Myochin Shikibu Ki (no) Munesuke.
The Myochin family are believed to have been makers of iron horse equipment during the Muromachi period, and became armourers during the late 16th century. They became well established in competition with the Haruta and Iwai families who were official armourers to the Tokugawa shogun, and made fine helmets signed by highly-regarded makers like Nobuie who is sometimes said to have been the first of the family. In 1680 Myochin Munesuke (1642-c.1735), the maker of this helmet, published a genealogy of the family, the ‘Myochin Rekidai Zokufu’ with a fictitious list of supposed ancestors reaching back several centuries and from then on the family flourished forming branch schools in the provinces. Sometime during the middle Edo period the Myochin grew in confidence to style themselves ‘On Katchu no Kiwame-dokoro, Nippon Yuitsu no Katchu no Ryoko’ [official appraisers of armour - the best armourers in Japan], and this is sometimes found inscribed on their work. By the middle Edo period the Myochin were well known for their manufacture of all components of armour from iron plate, often decorated with inlay or embossing. Myochin work reached its high standard of excellence largely due to the energy and skill of Munesuke, perhaps the greatest of the Edo Myochin, who actively promoted the name of the school. Munesuke was the first of several generations of skilful makers of armour, articulated iron animals (see lots 128, 129 and 130), and tsuba [sword guards] using the name Shikibu up to the Meiji period, and the work of the first generation is perhaps the highest-prized of all.